Biomedical subjects

Y He

Publications and source records attributed to Y He.

At least 163 records · Page 9Linked to original sources

PubMed2000

Calcitonin gene-related peptide in Langerhans cells in psoriatic plaque lesions.

OBJECTIVE: To study the mechanism of stress exacerbating psoriasis and the involvement effect of neuropeptides in psoriatic pathogenesis, we investigated the expression and secretion of calcitonin gene-related peptide (CGRP) in psoriatic lesions, then identified the target cells of CGRP, the characters of CGRP positive dendrite cells and the source of CGRP in psoriatic plaque lesions. METHODS: Specific radioimmunoassay (RIA) and immunohistochemistry staining methods were used to determine CGRP secretive content and the target cells of CGRP in psoriatic plaque lesion tissue of vulgaris psoriasis. Double immunofluorenscence staining was done on psoriatic plaque lesion sections by first using rabbit anti-human CGRP antibody and mouse anti-human CD1a antibody, second using PE-conjugated anti-mouse immunoglobulin and FITC-conjugated anti-rabbit immunoglobulin. Confocal laser microscope showed the psoriatic lesion sections. Then both digoxigenin labelled anti-sense and sense RNA probe of CGRP were synthesized to make sure the source of CGRP on the dendrite cells. The psoriatic lesion sections were studied by in situ hybridization. RESULTS: The content of CGRP in vulgaris psoriatic plaque lesions was higher than that of normal controls (P < 0.01). CGRP was also found on the dermal microvascular endothelial cells and the epidermal dendrite cells in psoriatic plague lesions. Further study showed that CGRP existed on the surface of epidermal CD1a + Langerhans cell in psoriatic plaque lesion. The CGRP mRNA expressed around the nucleus of the Langerhans cells in psoriatic lesion. CONCLUSIONS: The pathogenesis of psoriatic plaque lesions was closely related to the overexpression of neuropeptide CGRP. The CGRP contacted with the dermal microvascular endothelial cells and epidermal dendrite cells in psoriatic plaque lesion. The CGRP positive epidermal dendrite cell was CD1a + Langerhans cell. The Langerhans cell itself expressed CGRP mRNA.

Adult↗

PubMed2000

The role of c-myc in regulating mdr1 gene expression in tumor cell line KB.

OBJECTIVE: To investigate the relationship between c-myc expression and mdr1 regulation in multidrug resistance (MDR) tumor cell line KBv200. METHODS: A DNA sequence encoding the ribozyme gene was incorporated into a eukaryotic expression vector (pH beta Apr-1 neo) and transfected into the cell line KB, which is resistant to vincristine and expresses the MDR phenotype. The changes of c-myc protein, P-glycoprotein (P-gp) and c-myc mRNA in the KB cell line were assessed before and after treatment with anti-mdr1-ribozyme using immunohisto-chemistry, flow cytometry and semi-quantitative RT-PCR methods. RESULTS: The results demonstrate elevated levels of c-myc mRNA and c-myc protein as well as P-gp in KBv200 cells which are resistant to vincristine (VCR), compared to these of the KB cell which is not resistant to VCR. The expression of c-myc protein, P-gp and c-myc mRNA in the multidrug resistant cell, KBv200, displayed higher than that in the sensitive cell, KB. However, after reversing the multidrug resistance phenotype by anti-mdr1-ribozyme, the level of c-myc protein, P-gp and c-myc mRNA expression showed significant down-regulation in KBv/5 mR3, without difference in KB/5 mR3 and KB. CONCLUSION: The results of our study suggest that there is a close relationship between c-myc gene and mdr1 gene. c-myc may be involved in regulating the expression of mdr1.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2000

[Nasea injection in the prophylaxis of gastrointestinal reaction induced by chemotherapeutic agents].

OBJECTIVE: To evaluate the efficacy and side effects of nasea injection for the prophylaxis of gastrointestinal reactions induced by chemotherapeutic agents, and compare them with those of kytril. METHODS: A multicenter, open, randomized self-crossover control trial was carried out. All the eligible patients were randomized into AB or BA group. The patients in AB group were treated by nasea in the first cycle and kytril in the second cycle, those in BA group were treated with the drugs in the reverse order. RESULTS: In patients enrolled in this study, 98 patients were evaluable for response, including 61 patients in DDP-arm and 37 in ADM-arm. Nasea was as effective as kytril in the control of anorexia, nausea and vomiting in the 0-6 hour period after chemotherapy. Nasea was significantly superior to kytril in the complete control of anorexia (38.8% vs 25.5%, P < 0.05) in the 0-24 hour period. The overall control rate of nausea by nasea in the 0-12, 0-18, and 0-24 hour period was 73.6%, 71.4%, 67.3%, respectively, which was significantly higher than that by kytril (65.3%, 61.2%, 48%). Nevertheless, in the control of vomiting in the 0-24 hour period, no statistical difference between the two drugs was observed. Nasea and kytril were equally effective in the control of anorexia, nausea and vomiting induced by DDP and ADM. The side effects of nasea were head heaviness, headache, dry mouth and constipation, etc. All of these were mild and comparable with kytril in their frequencies. CONCLUSION: Nasea can effectively prevent the gastrointestinal reaction induced by chemotherapeutic agents. The side effects of nasea are similar to those of kytril but its effect to alleviate gastrointestinal reactions is of longer duration.

Adolescent↗

PubMed2000

[Prevalence of cag A and vac A subtypes of Helicobacter pylori in Guangzhou].

OBJECTIVE: To investigate the prevalence of cytotoxin associated gene (cag A) and vacuolating cytotoxin gene (vac A) subtypes of Helicobacter pylori (Hp) from patients with upper gastrointestinal diseases in Guangzhou, and to assess the relationship between cag A, vac A subtypes and Hp related gastrointestinal diseases. METHODS: 191 Hp strains were isolated from patients with different gastrointestinal diseases in Guangzhou. Bacterial DNA from all these strains was extracted. cag A and vac A alleles were typed using PCR with specific primers. RESULTS: In Guangzhou, Hp cag A positive rate was 85.3% (163/191). cag A positive rate was significantly higher in gastric cancer and peptic ulcer than that in chronic gastritis (P < 0.05). There were six vac A mosaicisms, including 168 for s1a/m2 (88.0%), 14 for s1a/m1b (7.3%), 6 for s1b/m2 (3.1%), 1 for s1b/m1b (0.5%), 1 for s2/m2 (0.5%) and 1 for s1a/m1b-m2 (0.5%). The rate of vac A s1a/m2 subtype in chronic gastritis, peptic ulcer and gastric carcinomas was 87.5% (70/80), 87.5% (84/96) and 93.3% (14/15) respectively. There was no significant relationship between cag A and vac A subtypes (P > 0.05). CONCLUSION: cag A(+) and vac A s1a/m2 subtype of Hp is predominant in patients with upper gastrointestinal diseases in Guangzhou, cag A(+) strains are further more common in patients with gastric cancer and peptic ulcer.

Adolescent↗

PubMed2000

[Hematopoietic stem cell transplantation for beta-thalassemia major].

OBJECTIVE: To discuss the feasibility of hematopoietic stem cell transplantation for beta-thalassemia major. METHODS: Bone marrow or cord blood of sibling was transplanted to 4 children with thalassemia, whose type of gene mutations was homozygous. All of them were diagnosed as beta-thalassemia major. HLA type was matched in 2 cases, and mismatched with 1 locus in the other 2. RBC type was mismatched in 1 cases. Pretransplant condition including busulfan (BU) 16 mg/kg, cyclophosphamide (CY) 200 mg/kg and anti-thymocyte globulin (ATG) 90 mg/kg. Graft-versus-host disease (GVHD) prophylaxis was cyclosporine-A (Cs-A) and methotrexate (MTX). RESULTS: Two Children had "serum sickness" during pretransplant condition; two children had grade II acute GVHD and 1 developed chronic GVHD, 1 case veno-occlusive disease (VOD), 1 case cytomegalovirus (CMV) interstitial pneumonia and 1 case fungemia post-transplant, which had been cured. The average time for peripheral WBC recovery > 1.0 x 10(9)/L was 16 days, 18 days for neutrophile granulocyte > 0.5 x 10(9)/L, 59 days for Plt > 50 x 10(9)/L and 39 days for Hb > 100 g/L. The average time for WBC recovery to normal was at day 24. The average time of last blood transfusion for patients was 29 days. The patients had to receive about 100 ml blood infusion per 2 months pretransplant, while not infused for 7 approximately 15 months up to now with Hb > 100 g/L. Gene mutation type of patients had changed to donor's. CONCLUSION: We report a successful transplantation of bone marrow and cord blood stem cells for thalassemia major in China. This will give a new strategy for treatment of the disease and further expand the use of stem cells transplantation.

Child, Preschool↗

PubMed2000

[Cloning and expression analysis of human dystonia/deafness peptide like gene].

OBJECTIVE: To clone a new deafness associated gene. METHODS: Molecular database search, RACE and cDNA library screen were applied. RESULTS: A new gene, named dystonia/deafness peptide like (DDPL) (GeneBank Accession Number: DDPL2 AF165967) and mapped to 11q22.1-22.2, was cloned. DDPL had two different mRNA splicing types and accordingly encoded 83 and 51 amino acids. DDPL transcripts were detected in a range of adult and fetal tissues. A pseudogene of DDPL, named DDPLphi which was shown lying within Xq25-q26, showed 96.9% sequence identity with DDPL1 cDNA sequence across 382 bp. CONCLUSION: DDPL lies within the 5.2 Mb interval of 11q22.1-q22.2 between D11S939 and D11S1347, and has a high identity with the DFN-1/MTS associated gene-DDP.

Adult↗

PubMed2000

[Cause and management of dislocated nuclear fragments during phacoemulsification].

OBJECTIVE: To investigate the cause and management of posteriorly dislocated lens nucleus in the vitreous cavity during phacoemulsification. METHODS: The authors performed a retrospective study of 18 patients with dislocation of nuclear fragment into vitreous cavity during phacoemulsification at Tong Ren Hospital from August 1994 to January 1999. RESULTS: 4 cases with dislocated nuclei floated in the anterior vitreous were removed by a lens loop from limbal extensive incision. 2 cases with their dislocated nuclei less than 1/4 of the normal size were under follow-up for 3 - 4 years, and no complications were observed. The final outcome in 1 case with a dislocated nucleus half of its normal size was ocular atrophy as a result of phacoanaphylactic endophthalmitis. 11 cases underwent pars plana vitrectomy. In the operation the nuclei were floated anteriorly by injection of perfluoro-1, 3-dimethylcyclohexane, then they were removed by a lens loop through the limbus and in 2 cases they were fragmented by ultrasound. The main post-operative complication was corneal edema. The final visual acuities generally were improved in varying degrees in 1 month to 4 years of follow-up. CONCLUSIONS: During phacoemulsification, the dislocation of a nucleus is liable to first occur in the peripheral sculpting stage, and secondly in central sculpting stage. A radial tear extending posteriorly from a discontinuous anterior capsulorrhexis is the major risk factor predisposing to posterior dislocation of the nucleus or nuclear fragment. During phacoemulsification, vitrectomy should be performed as soon as possible for a nucleus dislocated into middle or posterior vitreous cavity, and it is a safe and effective method for management of dislocated nucleus.

Adult↗

PubMed2000

[The clinical features and study on therapeutic effects of fungal keratitis].

OBJECTIVE: To review the clinical features and therapeutic effects of fungal keratitis (FK). METHODS: 110 cases (110 eyes) with the disease were divided into two types: hyphomycetic keratitis in 94 eyes and candida keratitis in 16 eyes. The clinical features and therapeutic effects of the two types were observed and compared. RESULTS: The hyphomycetic keratitis generally had a plant traumatic history. The border of corneal infiltration was not clear with feather edges, and had a tendency to penetrate into the deep stroma of cornea. There were endothelial plaques, hypopyon and bad therapeutic effects. The pathogenicity of cardida keratitis (CK) was related to the local long-term use of glucocorticoid, the fungus seldom expanded into the deep corneal layers and infiltrated into the inner eye. Its therapeutic effects were better. The border of CK was characterized with limitations, and was clear. CONCLUSIONS: The clinical features of the two types are different. The clinical features caused by different or the same pathogenic fungi show great variations. Early diagnoses, correct use of medicine and operation are the key points to increase the curative rate.

Adolescent↗

PubMed2000

[Studies on metal porphyrins as two-functional mimic of enzyme].

In this study, four metal porphyrins (tetraphenylporphyrinesulfonatoiron, tetraphenylporphyrinesulfon-atocopper, tetraphenylporphyrinesulfonatomanganese, and tetraphenyl porrphyrinesulfonatocobalt) were used as dual function mimicry of superoxide dismutase (SOD) and catalase (CAT). The first function, scavenging O2.-, has been proved by using riboflavine-methionine photoreduction method in the concentration range of 10(-5)-10(-6) mol/L. The second function, scavenging H2O2, has been demonstrated by means of spectrophotometry, and the percentage of decomposing H2O2 increases with the concentration of the imitating compounds. Metal porphyrins, SOD and CAT were measured by the liver homogenate technique of mice and the results showed that they had obvious action of decreasing the lipid peroxidation. Tetraphenylporphyrinesulfonatomanganese was measured by isolated ischemia reperfusion heart of rats. The results indicated that the Mn-TPPS4 could reduce the damages of active oxygen and had evidently protective effects on isolated ischemia-reperfusion mocardium of rats.

Animals↗

PubMed2000

[Clinical effects of intra-arterial nitrogen mustard (NH2) chemotherapy during operation for oral cancer].

OBJECTIVE: To discuss the general and local side-effects and clinic appliance of the intra-arterial chemotherapy, and evaluate the short-time clinic effects of the intra-arterial chemotherapy. METHODS: From February, 1997 to December, 1997 11 patients with oral cancer (9 cases with lingual carcinoma, 2 cases with mouth carcinoma) were received one-shot chemotherapy during operation by NH2 catheterizing of lingual arteries (concentration of 1 mg/ml, dosage of 5 mg), and the other 16 oral cancer patients (13 cases with lingual carcinoma, 3 cases with mouth carcinoma) were only received operation as the control. At the same time, all patients were treated with Chinese flaps or Major pectoris myocutanous flaps homochronously. Then the general and local side-effects including the flap complexion were observed 1 week post-operatively and the follow-up was done in a shot time of 3-12 months. RESULTS: No obvious general and local side-effects (including blood, mal function of liver and kidney, flap complexion, vomit and hemiplegia) happened and all the 11 flaps (6 Chinese flaps, 5 major pectoris myocutanous flaps) were alive in the experimental group. The local recurrent rate of the experimental group was 9.1%, while the rate was 18.8% in the control group (following up of 3-12 months). There was no significant difference between the experiment and the control groups by Student t-test. CONCLUSION: The one-shot chemotherapy intra-operationally is a method with few side-effects, and it doesn't injure the homochronously reconstructed flaps. It might be an effective means of reducing the local recurrence of oral cancer.

Adult↗

PubMed2000

[A study on the association of telomere length with the experimental carcinogenesis of oral cavity].

OBJECTIVE: The life cycle of cell can be effected by the length of telomere. Loss of telomeric DNA during cell proliferation may play a role in chromosome instability, cellular apoptosis and cancer. The purpose of the study is to measure the dynamic changes of telomere length in experimental oral cavity cancer during golden hamster cheek pouch carcinogenesis induced by DMBA. METHODS: First, 52 golden hamsters were divided into 2 groups. Four of them were not done any treatment and were killed after 3 days. The others were covered with DMBA on the surface of cheek pouch on one side in order to induce carcinogenesis, the other side of cheek pouch was treated as the control. Then, the 48 golden hamsters were divided into 4 groups and were killed in 7, 10, 14, 20 weeks. Light microscope was used to observe the pathologic changes. Southern hybridization was used to analysis the dynamic development of the length of telomeric repeat. In different periods, the reduction rate of telomere length was calculated. RESULTS: 1. The cheek pouch mucosa uncovered with DMBA had no abnormal pathologic changes, while that covered with DMBA was observed pathologic changes of different degrees. 4 cases of hyperplasia lesions and 8 cases of dysplasia lesions were observed in the 7-week group, 7 cases of dysplasia lesions and 5 cases of mucosa carcinoma in situ in the 10-week group, 5 cases of mucosa carcinoma in situ, 4 cases of squamous cell carcinomas and 3 cases of death in the 14-week group, and 7 cases of squamous cell carcinomas and 5 cases of death in the 20-week group. 2. The telomere length of the normal mucosa was reduced with the hamsters age increasing, but the telomere length was significantly shorter than that of the normal control during the mucosa carcinogenesis of cheek pouch. The average shortened length was about 0.225 kb (the normal mucosa was 0.17 kb). 3. The highest reduction rate (0.3985) was in a later premalignant period. CONCLUSION: Age is one of the factors that can short telomere length. However, the speed that telomere length is shorted is faster than ever while telomere is abnormal. There is an obvious relationship between the abnormal degree of telomere length and the malignant degree of carcinoma. So the abnormal shorting of telomere length is an early molecular evidence of the oral carcinogenesis.

Animals↗

PubMed2000

[Identification of telomerase activity in the experimental carcinogenesis of oral cavity].

OBJECTIVE: Telomerase is a ribonucleoprotein enzyme which synthesizes telomere DNA repeat sequences and maintain stably telomere length. The activity of telomerase may be necessary for the growth of immortalized cells overcoming cellular senescence. The researches have shown that telomerase activities are associated with most cancers. The purpose of the study is to detect the development of telomerase activity during golden hamster cheek pouch carcinogenesis induced by DMBA. METHODS: First, 52 golden hamsters were divided into 2 groups. Four of them were not done any special treatment and were killed after 3 days. The others were covered with DMBA on the surface of cheek pouch on one side in order to induce carcinogenesis, the other side of cheek pouch was treated as the control. Then, the 48 golden hamsters were divided into 4 groups and were killed in 7, 10, 14 and 20 weeks. The telomeric repeat amplification protocol (TRAP) based on PCR and ELISA was used to analysis the activity of telomerase. RESULTS: 1. The expression of telomerase activity existed in normal cheek pouch mucosa of golden hamsters, which meant that telomerase played an important role on controlling cell proliferation. 2. The level of telomerase activity gradually increased while hyperplasia and dysplasia was observed in the cheek pouch mucosa covered with DMBA. It reached its top at a later premalignant period and gradually decreased after that. 3. There was negative correlation between the degree the telomere length was shortened and the activity of telomerase (r = -0.9654), and there was positive correlation between the reduced rate of telomere length and the activity of telomerase (r = 0.9471). CONCLUSION: The activity of telomerase is one of important factors that can effect the stability of telomere length and plays a crucial role in the progression of oral cancer. So the activity of telomerase is an early molecular marker of carcinogenesis.

Animals↗

PubMed2000

[Study on the relationship between the abnormal expression of c-myc and multidrug resistance in KB cell lines].

OBJECTIVE: To investigate the relationship between expression of c-myc and the regulation of mdr1, and find out the best way for gene therapy of the proliferative diseases with c-myc overexpression and reverse the multidrug resistance phenotype. METHODS: The changes of c-Myc protein and P-gp in the KB cell lines were detected by using immunohistochemistry and flow cytometry methods before and after treatment with anti-mdr1- ribozyme. RESULTS: All KB cell lines could express c-Myc protein. The expression of c-myc in multidrug resistant cell KBv displayed higher than that in sensitive cell KB. However, after reversing the multidrug resistance phenotype by anti-mdr1-ribozyme, the level of c-Myc protein expression was lower in KBv/5mR3 and KB/5mR3. The level of P-gp expression was lower in KBv/5mR3 than that in KBv but no difference in KB/5mR3 and KB. CONCLUSION: There are a close relationship between Myc protein and MDR phenotype. The c-myc involves in regulating expression of mdr1. Myc protein can be used as a new assistant implement to monitor the formation of MDR.

ATP Binding Cassette Transporter, Subfamily B↗

PubMed1999

New synthetic technology for the synthesis of hindered alpha-diazoketones via acyl mesylates.

[formula: see text] A mild and reliable one-pot protocol for the elaboration of sterically demanding carboxylic acids into alpha-diazoketones via acyl mesylates has been developed. Aside from delineating the reaction parameters which render this strategy quite general for hindered carboxylic acids, we have directly proven the existence of the fleeting acyl mesylate group as the reactive species in these reactions and shed light onto the differing mechanisms which are operative in the activation of hindered and simple carboxylic acids with methanesulfonyl chloride.

Ketones↗

PubMed1999

Measuring recent thymic emigrants in blood of normal and HIV-1-infected individuals before and after effective therapy.

The role of the thymus in HIV-1 pathogenesis remains unclear. We developed an assay to quantify the number of recent thymic emigrants in blood based on the detection of a major excisional DNA byproduct (termed alpha1 circle) of T cell receptor rearrangement. By studying 532 normal individuals, we found that alpha1 circle numbers in blood remain high for the first 10-15 yr of life, a sharp drop is seen in the late teen years, and a gradual decline occurs thereafter. Compared with age-matched uninfected control individuals, alpha1 circle numbers in HIV-1-infected adults were significantly reduced; however, there were many individuals with normal alpha1 circle numbers. In 74 individuals receiving highly active antiretroviral therapy, we found no appreciable effect on alpha1 circle numbers in those whose baseline values were already within the normal range, but significant increases were observed in those with a preexisting impairment. The increases in alpha1 circle numbers were, however, numerically insufficient to account for the rise in levels of naive T lymphocytes. Overall, it is difficult to invoke thymic regenerative failure as a generalized mechanism for CD4 lymphocyte depletion in HIV-1 infection, as alpha1 circle numbers are normal in a substantial subset of HIV-1-infected individuals.

Adolescent↗

PubMed1999

A putative exchange factor for Rho1 GTPase is required for initiation of cytokinesis in Drosophila.

Cytokinesis ensures the successful completion of the cell cycle and distribution of chromosomes, organelles, and cytoplasm between daughter cells. It is accomplished by formation and constriction of an actomyosin contractile ring that drives the progression of a cleavage furrow. Microinjection experiments and in vitro transfection assays have suggested a requirement for small GTPases of the Rho family in cytokinesis. Yet, the identity of proteins regulating Rho signaling pathways during cytokinesis remains unknown. Here we show that in Drosophila, Pebble (Pbl), a putative exchange factor for Rho GTPases (RhoGEF), is required for the formation of the contractile ring and initiation of cytokinesis. The dynamics of Pbl expression and its distribution during mitosis, as well as structure-function analysis, indicate that it is a key regulatory component of the pathway. pbl interacts genetically with Rho1, but not with Rac1 or Cdc42, and Pbl and Rho1 proteins interact in vivo in yeast. Similar to mutations in pbl, loss of Rho1 or expression of a dominant-negative Rho1 blocks cytokinesis. Our results identify Pbl as a RhoGEF specifically required for cytokinesis and linked through Rho1 activity to the reorganization of the actin cytoskeleton at the cleavage furrow.

Amino Acid Sequence↗

PubMed1999

The single-channel dose-response relation is consistently steep for rod cyclic nucleotide-gated channels: implications for the interpretation of macroscopic dose-response relations.

Cyclic nucleotide-gated channels contain four subunits, each with a C-terminal binding site for cGMP or cAMP. The dose-response relation for activation is usually fit with the Hill equation, I/I(max) = [cGMP]n/([cGMP]n + K(1/2)n, where I/I(max) is the fraction of maximal current, K(1/2) is the concentration of cGMP that gives a half-maximal current, and n is the Hill coefficient, taken as the minimum number of ligands required for significant activation. The dose-response relations in multichannel patches are often fit with Hill coefficients of </=2.0, even though other lines of evidence indicate that these channels contain four binding sites and that the binding of three or four ligands is required for significant opening. We have measured dose-response relations for a large number of single cyclic nucleotide-gated channels composed of the bovine rod alpha subunit. We find that the single-channel Hill coefficient is consistently higher than 2.5, with an average of 3.0 +/- 0.37 over 16 patches. In both multichannel and single-channel patches, large variations in K(1/2) have been observed, and are thought to arise from modifications such as phosphorylation. Here we show that mixtures of single channels with high Hill coefficients and variable K(1/2) values will give rise to shallow macroscopic dose-response relations with anomalously low Hill coefficients. This is because activation occurs over a broad range of cGMP concentrations. Thus, dose-response relations from multichannel patches should be interpreted with caution, particularly when detailed mechanistic issues such as cooperativity are being investigated.

Animals↗

PubMed1999

Novel strategies to construct the gamma-hydroxy lactone moiety of the CP molecules. Synthesis of the CP-225,917 core skeleton.

[formula: see text] The array of challenging structural lineaments embodied in the CP molecules (1 and 2, Figure 1) offers synthetic chemists uncharted realms of exploration and discovery. In this communication, we focus on the chemical hurdies posed by the gamma-hydroxy lactone moiety of these exciting targets. Thus, the examination of the general reactivity of these systems, the development of a novel tandem oxidation sequence to construct the gamma-hydroxy lactone moiety, and the successful construction of the complete polycyclic core of 2 (compound 28, Scheme 5) is enumerated within.

Enzyme Inhibitors↗